The Centers for Disease Control and Prevention has reopened an investigation into an outbreak of drug-resistant salmonella in people linked to Wisconsin calves.
The CDC stopped the investigation in March, when 15 of 36 cases from 10 states were from Wisconsin, because the outbreak appeared to be over.
But 10 cases have been reported since April, prompting the renewed probe. None of the new cases are from Wisconsin. A total of 46 cases have now been reported from 14 states.
The Wisconsin cases, the last of which was reported in December, have been from nine counties: Chippewa, Clark, Eau Claire, Lafayette, Marathon, Ozaukee, Rock, Rusk and Trempealeau, said Jennifer Miller, spokeswoman for the state Department of Health Services.
The department “continues to collaborate with other state agencies to do surveillance for both human and animal cases,” Miller said.
The disease strain involved in the outbreak, salmonella Heidelberg, was discovered in July 2016 after a 16-year-old boy became ill after buying calves from a Wisconsin dealer for a 4-H project.
Salmonellosis is a bacterial infection that generally affects the intestinal tract and occasionally affects the urine, the bloodstream or other body tissues. It is a common cause of diarrhea in Wisconsin.
Of the 46 cases, 15 are among children under age 5 and 14 have been hospitalized. No deaths have been reported.
The infections are resistant to commonly used antibiotics, but other antibiotics can be taken if the particular strain of salmonella is confirmed.
Many of the cases are linked to contact with dairy bull calves, male cattle that may be raised for meat. Many of the patients said they became sick after their dairy bull calves became sick or died.
Health officials say farmers should wash their hands after touching livestock, equipment or anything in the area where animals live and roam. Farmers should also use dedicated clothes, shoes and work gloves when working with livestock, and keep and store these items outside of their homes.